Best wooden mast finish?

[Boracay]

I haven't done a mast but I've bolted all sorts of wooden bits and pieces to Boracay over the last few years. Some have rotted and some have held up well.

Surprisingly a good thick coat of epoxy with a nice pad of polyurethane mastic under lasts OK when bolted to steel. The wood must always be well electrically insulated from the steel. It is of course much better to weld a stainless steel tang to the steel and then to bolt to that but expediency sometimes gets in the way.

However the finish that has lasted best of all has been a single layer of fibreglass epoxied over the top of the wood. Mostly it's been a variety of white paints on top of that, just to protect the epoxy.

I'll concur with the poster who notes that a plain epoxy coat will split if even a trace of moisture gets into the wood.

I've experimented a bit with concentrated ethylene glycol (antifreeze) solution. It does seem to stop the rot but I wonder how well epoxy will bond to the wood if it's used as a first step?

[JoeFish]

Originally Posted by Cheechako

Spar varnish like McCloskeys or similar. It stays more flexible than plain varnish.

That's a characteristic of all spar varnish. It's typically formulated to remain somewhat soft and 'heal' if scratched or damaged without outside assistance (this is perhaps the most important characteristic of spar varnish). Without this it would crack as soon as you sailed the boat.

In terms of it's overall performance, I have yet to find anything with a thinner film or better UV resistance than Epifanes. I will admit that it takes time to learn consistent application and it does not suffer mixing with off-brand solvents at all.

[sabray]

Bed and protect penetrations. Paint will last longer with less work. It's about the uv. Also depends on where you are if northern climes uv will be less of an issue. Waxing a mast while it makes sense is still a lot of work. Pretty sure if you decide to wax your mast as often as has been suggested you won't have time to be a major CF contributor.
If heading tword mid equator paint it and seal the penetrations. If not then epiphanies thinned and lots of coats. Wax it when you have spare time. But to tell us how it is going

[JoeFish]

Originally Posted by Boracay

I've experimented a bit with concentrated ethylene glycol (antifreeze) solution. It does seem to stop the rot but I wonder how well epoxy will bond to the wood if it's used as a first step?

If you can insure that there will never be a point of ingress for water at any point along the length of the spar then epoxy would be fine, but spars are full of fasteners, subject to constant flexing, chafing from sails, lines, halyards, etc. I would never tell a customer that I guarantee a spar free from water ingress on a mast exposed to the elements 24/7 for years on end.

I do paint under the hardware as a preventative measure as sabray pointed out it's a bit more durable over time. The colour we use is very close to the spar and we mask it so the hardware conceals it fully.

The real problem is most spars are stepped for one or more years between proper inspection. A lot of damage can be done before you find a problem and that could lead to deep extensive structural damage. That usually ends badly.

With a top quality wood spar costing many tens of thousands of dollars that's not a risk I'd be willing to take.

[JoeFish]

I should add; our case is likely different than most. Our boat is both a family cruiser and something of a museum piece. While we sail it hard, we intentionally chose to buy a boat about 6' shorter than our checkbook knowing that we wanted to keep her to a very high standard of finish.

Foot for foot we probably spend 2:1 what most owners do on maintenance and finish work (400+ hours of fairing on the hull for the new paint job was a prime example of that).

In the end each climate and owner will dictate the best approach to varnish, what I do know is that my recommendations come after owning two classic yachts over more than 20 years, one in the PNW, the other in the Northeast.

We've always had very good results with this approach and the durability has more than satisfied me.

[model 10]

It's nice that you told us where you are from because living up north has almost no bearing on living with varnish in the sun.

[JoeFish]

When we were in the Northeast the other boat went south every year in November via Bermuda to the Caribbean. It lived there until usually late April or early May.

We had awnings and some covers for things like hatches and dorade boxes. In those years we applied one more coat in February while down south, otherwise things held up fine.